2021 BMW M340I Cooling System Parts

This table covers the engine coolants and antifreeze formulations specified for this cooling system. Typical signs include a rising temperature gauge, rusty or sludged coolant, or a heater that blows cold. Use the chemistry named in the notes. Mixing silicate, OAT and HOAT formulas can gel in the radiator. Read more

11 Coolant / Antifreeze parts for the 2021 BMW M340I come from 4 brands — PRESTONE, PEAK, AISIN and 1 other brand. The "Popular" part is PRESTONE AF3100.

In the Compatible With All Colors grade, PRESTONE supplies 1 part: grouped under the catalog's "Compatible With All Colors" designation — the notes column spells out what sets them apart. A representative part number is PRESTONE AF3055.

The Economy section lists 2 options from PRESTONE and PEAK — the catalog's value-priced group. PRESTONE AF3100 is listed in this group.

In the Premium grade, PRESTONE and PEAK supply 5 parts: a step above OE specification in materials, tolerances or warranty terms. A representative part number is PRESTONE AF2100.

In the Standard Replacement grade, AISIN, PEAK and VALVOLINE supply 3 parts: built to original-equipment specification. A representative part number is AISIN ACE008.

This table covers the bleeders used to purge air from the coolant circuit. Read more

DORMAN supplies both parts for the 2021 BMW M340I.

Listed part numbers: DORMAN 902404 and DORMAN 902404HP.

This table covers the overflow / expansion tanks that hold extra coolant. Read more

5 Coolant Reservoir parts are listed for the 2021 BMW M340I, from TECHPRO and MAHLE / CLEVITE. TECHPRO BM3014121 carries the "Popular" badge.

Part numbers include TECHPRO BM3014121, MAHLE / CLEVITE CRT299000S and MAHLE / CLEVITE CRT254000S, among others listed above.

This table covers the caps on the overflow / expansion tank. Typical signs include a leak at the neck, a cap that will not hold pressure, or a missing tether. Match the pressure rating or thread in the notes — radiator, reservoir and fuel caps are not interchangeable. Read more

5 Coolant Reservoir Cap parts are listed for the 2021 BMW M340I, from MOTORAD, CALORSTAT, REIN and 1 other brand. MOTORAD T64 carries the "Popular" badge.

Listed part numbers: MOTORAD T64, CALORSTAT RC0084 and MOTORAD T76, plus the other parts above.

This table covers the radiators that dump engine heat to airflow through the core. Typical signs include overheating in traffic, a wet core, or coolant that disappears with no puddle. Replace the cap if it cannot hold the rated pressure, and bleed the system after the swap. Read more

5 Radiator parts for the 2021 BMW M340I come from 4 brands — NISSENS, GPD, TYC and 1 other brand. The "Popular" part is TYC 13845.

The Economy section: 1 option from GPD. GPD 13798C is listed in this group.

Standard Replacement: 4 parts, from NISSENS, TYC and UAC. A representative part number is TYC 13845.

This group includes TYC 13845, GPD 13798C and NISSENS 606784 and the remaining parts above.

This table covers the fan assemblies (and clutches, where listed) that pull air through the radiator. Read more

3 Radiator Fan Assembly parts are listed for the 2021 BMW M340I, from TECHPRO and VDO / CONTINENTAL.

Economy: 2 parts, from TECHPRO. A representative part number is TECHPRO BM3115145.

The Standard Replacement section: 1 option from VDO / CONTINENTAL. VDO / CONTINENTAL FA74027 is listed in this group.

Part numbers include TECHPRO BM3115145, TECHPRO BM3115148 and VDO / CONTINENTAL FA74027.

This table covers the senders that report coolant temperature to the gauge or ECU. Typical signs include a gauge that sits on empty or overheat, or a lamp that does not match what the engine is doing. Rule out the cluster and the wiring before replacing the sender. Read more

9 Temperature Sender / Sensor parts for the 2021 BMW M340I come from 6 brands — WALKER PRODUCTS, GPD, VEMO and 3 other brands. The "Popular" part is GPD 1814545.

The Economy section: 3 options from GPD and VEMO. GPD 1814545 is listed in this group.

Standard Replacement: 6 parts, from WALKER PRODUCTS, FACET, STANDARD MOTOR PRODUCTS and 1 other brand. A representative part number is WALKER PRODUCTS 2112021.

This group includes GPD 1814545, GPD 1814574 and VEMO V20720201 and the remaining parts above.

This table covers the thermostats that open the coolant circuit at the specified temperature. Typical signs include slow warm-up, a gauge that climbs in traffic, or heat that never quite arrives. Replace the housing gasket with the thermostat and bleed the system so a trapped air pocket does not cook the new part. Read more

3 Thermostat parts are listed for the 2021 BMW M340I, from SKP, MOTORAD and INA.

Economy: 1 part, from SKP. A representative part number is SKP SK1120221.

The Standard Replacement section: 1 option from MOTORAD. MOTORAD 1120221 is listed in this group.

1 ungrouped part is not assigned to a grade, with the same engine-level match.

Part numbers include SKP SK1120221, MOTORAD 1120221 and INA XW0811.

This table covers the housings and outlets the thermostat sits in. Read more

One part is listed for the 2021 BMW M340I — VEMO V20990005.

This table covers the pumps that circulate coolant through the block and radiator. Typical signs include coolant at the weep hole, pulley play, or a growl from the front of the engine. Replace the thermostat and refill with the specified coolant whenever the pump comes off. Read more

4 Water Pump parts are listed for the 2021 BMW M340I, from BOSCH, FVP, GMB and 1 other brand.

Listed part numbers: BOSCH 0392023486 and FVP 1153380, plus the other parts above.

This table covers the gaskets between the water pump and the block or housing. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

2 Water Pump Gasket parts for the 2021 BMW M340I come from 2 brands — AJUSA and ELRING.

Part numbers include AJUSA 01732500 and ELRING 113600.